The obesity pandemic – A major threat to global health and wellbeing

There is an obesity pandemic, a chronic disease associated with a high risk of health disorders, including diabetes mellitus, heart disease, hypertension, dyslipidaemia, musculoskeletal disorders, sleep disorders and multiple types of cancer.

Conversely, a weight loss of at least 5 – 10 per cent can significantly improve health-related outcomes in obese patients. Currently, a 5 – 10 per cent weight loss over 6 months is considered a realistic goal with proven health benefits.

Obesity is defined by the World Health Organisation (WHO) as “an abnormal or excessive fat accumulation that presents a health risk,” and it is further classified in adults as a BMI of 30 or higher (Overweight is a condition of excessive fat deposits).

A state of positive energy balance exists in the duration of the energy intake exceeding energy consumption, resulting in the storage of the excess calories in adipose tissue, which first leads to body phenotypic overweight (body mass index, BMI 25-30 kg/m2). It then develops into a weight disorder called obesity, defined as a BMI ≥30 kg/m2.

Measurement

The diagnosis of overweight and obesity is made by measuring people’s weight and height and by calculating the body mass index (BMI): weight (kg)/height (m²). The body mass index is a surrogate marker of fatness and additional measurements such as the waist circumference (and waist-to-hip ratio), which can help the diagnosis of obesity.

A ratio greater than 1.0 in men and greater than 0.85 in females defines the obese individual. In 2022, 1 in 8 people in the world were living with obesity. Worldwide adult obesity has more than doubled since 1990, and adolescent obesity has quadrupled.

In 2022, 2.5 billion adults (18 years and older) were overweight. Of these, 890 million were living with obesity. In 2022, 43 per cent of adults aged 18 years and over were overweight and 16 per cent were living with obesity.

In 2022, 37 million children under the age of 5 were overweight. Over 390 million children and adolescents aged 5–19 years were overweight in 2022, including 160 million who were living with obesity.

In Europe, the incidence of obesity is five times higher than it was after World War II and the number of obese people doubles yearly. A study of BRICS (Brazil, Russia, India, China, and South Africa) countries during 2007-2010 found that obesity was associated with hypertension, angina, diabetes and arthritis.

In Ghana, a study showed that the overall crude prevalence of overweight and obesity were 23.4 and 14.1 per cent among adults aged 25 years and above for urban and rural dwellers respectively.

The rates were higher in females than in men. Obesity increased with age up to 64 years. A ratio greater than 1.0 in men and greater than 0.85 in females defines the obese.  Obesity is by far the most important risk factor for type 2 diabetes (Biritwum et al. The Epidemiology of Obesity in Ghana. Ghana Med J. 2005 Sep; 39(3): 82–85).

The Ghana Demographic and Health Surveys (GDHS) from 1993 to 2014 reported an increasing prevalence of obesity among Ghanaian women (15–49 years) from 3.4 per cent to 15.3 per cent.

The WHO estimates that in 2008, around 7.5 per cent of Ghanaians were obese with a higher prevalence in women (10.9%) than men (4.1%) [(Ofori-Asenso et al. Overweight and obesity epidemic in Ghana – A systematic review and meta-analysis. December 2016. BMC Public Health 16(1). DOI:10.1186/s12889-016-3901-4

Evidence

Evidence shows that weight loss can significantly reduce the risk of obesity-related complications and chronic diseases. Diet control, moderate exercise, behaviour modification programmes, bariatric surgery and prescription drug treatment are all interventions used to help people lose weight.

Weight loss should first begin with behavioural and  lifestyle changes. In practice, many find it challenging for lifetime commitments required to gains made in weight loss. Such lapses in commitment result in weight gain and frustration.

About one-third to two-thirds of lost weight is regained within one year following the end of non-drug therapy and greater than 95 per cent of weight is regained within 5 years.

To patients who have failed to achieve clinically significant weight loss (defined as greater than or equal to 5 per cent of baseline weight after 6 months of lifestyle interventions), the recommendation is to start an anti-obesity medication (AOM) for BMI greater or equal to 30kg/m2 or BMI greater or equal to 27kg/m2 with co-morbidities.

Anti-obesity medications generally have high adherence rates and cause noticeable short-term effects in reducing obesity levels. Some of them have safety issues. Weight-loss surgery effectively reduces weight and complications in patients with severe obesity; however, weight gain is a common complication following surgery.

An intergalactic balloon (IGB) is a usually safe, reversible and less invasive way to cause weight loss based on occupying stomach space to increase satiety. However, regarding weight loss, the results of using IGBs cannot be compared with bariatric surgery.

Drug therapy for weight loss has made significant progress. However, many anti-obesity agents that have entered human clinical trials have shown unacceptable adverse events; many of them cannot be used for more than 3 months; the curative effect is moderate and suboptimal in the long term.

Medications approved by (FDA) for weight loss include Phentermine (short-term use), Diethylpropion (short-term use), Orlistat (long-term use), Phentermine-Topiramate (long-term use), Bupropion-Naltrexone (long-term use), Liraglutide (long-term use), Setmelanotide (long-term use), Semaglutide (long-term use), Gelesis 100 (long-term use!).

Orlistat is the only OTC medication that is FDA-approved for weight loss in conjunction with reduced calorie intake. The OTC version of Orlistat (60 mg) is indicated for overweight adults aged 18 years or older in conjunction with a reduced-calorie, low-fat diet.

Orlistat does not act systemically; instead, it exerts its therapeutic activity in the lumen of the stomach and small intestine by inhibiting gastric and pancreatic lipases that hydrolyse triglycerides into free fatty acids and monoglycerides.

This restricts the intestine’s ability to absorb triglycerides which are excreted fecally instead, thus inhibiting absorption of dietary fats by approximately 30 per cent. Liraglutide is an injectable glucagon-like peptide 1 (GLP-1) derivative.

After meals, GLP-1 is secreted from the distal ileum, proximal colon, and the vagal nucleus of the solitary tract and exhibits multiple effects as an incretin (intestinal secretion of insulin) hormone.

GLP-1 mainly regulates blood glucose by enhancing insulin secretion from the pancreatic beta-cells and inhibits glucagon secretion in a glucose-dependent manner. GLP-1 also induces postprandial satiety and fullness, slows gastric emptying and decreases appetite and food consumption by acting on the hypothalamus, limbic/reward system and cortex.

Unlike human GLP-1, Liraglutide is more stable in plasma and binds strongly to plasma proteins thereby enabling a much longer half-life. Apart from weight loss and reduction in blood sugar levels, Liraglutide also improves cardiovascular indicators such as blood pressure and lipid profiles.

The most frequent side effects are nausea, vomiting, diarrhoea, constipation and dyspepsia. Other molecules are working similarly to effect weight loss such as Semaglutide and tirzepatide.

At this point, allow me to add a product we are a major producer of– cocoa.  A polyphenol-rich cocoa diet promotes weight loss through lower adipose tissue synthesis and stimulation of cell energy expenditure. Polyphenol-rich cocoa has beneficial effects on satiety, cognitive function and mood.

The writer is a Pharmacist